1. Field of the Invention
The present invention relates to an automatic focusing method and an automatic focusing control function, which for example is configurable for use in a digital camera equipped with an automatic focusing function (commonly abbreviated as “auto focus function” or “AF function”).
2. Description of the Related Art
Recently, in step with the advances of digital camera technology, a digital camera with AF functions consistent with a hybrid method (also referred to as a “hybrid system”) which jointly utilizes a contrast AF function with a phase difference AF function has begun to appear in the electronic camera industry. Accordingly, AF processing can be performed rapidly with high precision.
In particular, after performing focus lens drive based on a phase difference detection signal by a phase difference detection method and then performing a focus lens drive based on an AF rating value by a contrast detection method, the apparatus is practically in a focused state in an incredibly short time. Furthermore, it is possible to produce a highly precise focus with a contrast detection method.
However, in a conventional digital camera, etc. using AF processing consistent with a hybrid method although a focus state can be rapidly realized and with high precision to shoot an object (take an image of a subject), when the AF sensor (ranging sensor) is obstructed (blocked from the field of view) there is a high probability that the snapshot will be flawed or the image could not be taken in a highly precise focus state.